1. Field of the Invention
The present invention relates to a multihead liquid emission recording apparatus, and more particularly relates to a multihead liquid emission recording apparatus suitable for use with such a device as a color image printer.
2. Description of the Prior Art
In a multihead liquid emission recording apparatus, if there is a difference of liquid-jet characteristics among a plurality of liquid emission heads, it has been inevitable that the diameter of each recording dot on a recording paper formed by the respective heads becomes unequal even if the same drive voltage is used for driving the respective heads. In addition, in the case that a high fidelity image is intended to be obtained by changing the dot diameter by changing the drive voltage for the respective heads (so-called analog modulation), even if the respective heads are driven within the same drive voltage variation range, the above mentioned inequality of the dot diameters has been a great obstacle to high image fidelity. In other words, there arises a problem in the case of a color image printer, since the density variation range on a recording paper is different for each head, the quality of a reproduced color image is degraded, and furthermore, the color tone obtained by each head is different from each other.
In such an apparatus, in order to make the jet characteristics uniform throughout the respective heads composing a multihead, some measures have been adopted. One of the measures is to manufacture a high precision head by improving the dimensional accuracy of the components constituting the head, such as electro-mechanical conversion elements, nozzles, and the like. Another of the measures is to determine each jet characteristic of independent heads and select heads having relatively similar characteristics so as to fabricate therefrom an integrated multihead. However, both of such measures have been found unsatisfactory because they produce an inevitable rise in cost.